Motor-controller.



L. L. TATUM.

MOTOR CONTROLLER.

APPLICATION man JAN. 8. 1913.

1 14 ,1 54. Patented June 1, 1915-.

2 sussrs suzzr 1.

L. L. TATUM. MOTOR CONTROLLER.

APPLICATION EILED JAN. 8, 1 9I3- 4, Eatented June 1, 1915.

' directions.

UNITED STATES PATENT OFFICE.

LEWIS I4. TATUM, OF MILWAUKEE, WISCONSIN, ASSIGNOB TO THE CUTLER-HAMMER MFG.CO., OF MILWAUKEE, WISCONSIN, A CORPORATION OF WISCONSIN.

MOTOR-CONTROLLER.

Specification of Letters Patent.

Patented J une- 1, 1915.

. Application filed January 8, 1913. Serial No. 740,760.

T all whom it may concern:

Be it known that I, Lnwrs L. TATUM, a citizen of the United States, residing at Milwaukee, in the county of Milwaukee and State of Wisconsin, have invented new and useful Improvements in Motor-Controllers, of which the following is a full, clear, concise, and exact description, reference being had to the accompanying drawing, forming a part of this specification.

My invention relates to improvements in controllers for electric motors.

My invention is particularly applicable '1) the control of motor operated washing machines and other machinery which it is desired to intermittently operate in opposite It should be understood, however, that certain features of my invention may be used in various other relations for various different purposes.

In order to fully and clearly disclose the I direction as long as the push button is held nature and advantages of my invention shall describe the embodiments thereof illustrated in the accompanying drawings, it of course being understood that my invention is susceptible of modifications.

In the accompanying drawings, Figure 1 is a diagrammatic view of a controller for machines operated by alternating current motors. Fig. 2 is a diagrammatic viewof a controller for machines operated by direct current motors.

The motors M shown in Fig. 1 are of the three-phase alternating current type, but of course in practice they might be of any other desired type. F or the purpose of the following description it may be assumed that the motors M operate separate washing machines, which it is desired to periodically reverse after a predetermined number of revolutions of the motors in each direction.

Each controller includes switches 1 and 2 controlling the continuity of the motor circuit and the direction of the fiow of current through the motor. One serves to-cause its respective motor to operate in a forward direction and the other serves to cause the motor to operate in a reverse direction. A

pilot switch 3 operated by the driven machine or by the driving motor serves to alter-' nately energize the switches 1 and 2 to insure. the periodic reversals of the motor.

motors M are controlled in an identical manner by their respective pilot switches 3 and are jointly controlled through similar circuits by the master pilot switch 4. A description of a single motor and its control will accordingly suffice to disclose the operation and control of all the motors. 'A doublepole double-throw switch 5 is provided to connect the switches 1 and 2 to either the individual pilot switch 3 or the group pilot switch 4. A double-pole switch 6, which in practice is preferably of the snap type, is

as I

provided for stopping and starting the motor at will. In addition to the foregoing, the controller is also provided with normally open push-buttons 7 and 8 controlling the operating windings of the switches land 2 independently of the pilot switches. By means of these switches the motor may be started in either direction at will. The motor will continue to operate in the same closed. The provision of these push-buttons is very advantageous where the controller is used for washing machines of the type having separate compartments in the washing drum. In such machines it is often desired to move the drum into a position to give access to some particular compartment. The attendant can tell from the position of the drum which direction of operation will most quickly bring'the drum into the desired po- These switches are preferably interlocked to prevent both being closed at the same time. Any preferred form of interlocking means may be employed for this purpose. The-1nterlock shown merely comprises a pivoted bar 10 coi iperatin'g with extensions onthe plungers of the operating solenoids of the switches 1 and 2- to lock the plunger of either switch against operation, upon operation of the other.

- engages Tn practice, the pilot switch 3 may be oi? any preferred type. As schematically illustrated in the drawing, it comprises contact rings 11, 12 and 13 mounted upon a revoluble shaft 1 The rings 11, 12 and 13 have cooperating brushes 11*, 12 and 13 respectively. The ring 11 comprises a continuous conductor, while the rings 12 and 13 have insulating portions extending slightly less than hal t-way around the same. The rings and 13 are so disposed with respect to one another on the shaft 1 that conducting section oi each will engage its respective contact brush just prior to the disengagement of the conducting section of the other from its respective brush. Thus, as the shaft lat is rotated, the circuits through the rin s 12 and 13 are completed and broken alternately. The shaft 14-. has keyed thereto a ratchet wheel 15 with which a reciprocating ratcheting bar 1% pivoted eccentrically to the reversing drum 17 of the operated machine. With this arrangement the shaft 1 is revolved in a step by step manner in a single direction so long as the driven machine is in operation. Of course, practice the'pilot switch 3 might be operated trom'either the machine or the driving motor in any other preferred man nor.

The group pilot switch 1 may in practice be of the ring type similar to the pilot switch 3 or an other preferred type. As illustrated, it 1s of the ring type, but in order to simplify the illustration thereof the rings have been shown as flat segments with the insulated sections omitted. This switch is provided with a continuous ring 18 corresponding to the ring 11 of the pilot switch 3 and with a plurality of pairs of rings 19 and 20 corresponding to the rings 12 and 13 of the pilot switch 3. Eachpair of rings 19 and 20, ascwill later be apparent, is adapted to control a separate machine and, of course, the pilot switch 4 may be provided with as many pairs of these rings as there are machines to be controlled. As will be observed from the drawing the several pairs of rings 19 and 20 are stag cred- The purpose of this arrangement Wlll be hereinafter. set forth. The pilot switch 4 is preferably driven continuously by independent means such as a motor 21. Ourrent is supplied to the motor and to the operating windings of the switches 1 and 2 from the source of alternating current sup ply, the lines of which have been designated as 25, 26 and 27. A triple-pole switch 28' is provided for connecting the controller to the source of supply and fuses 29, 30 and 31 are connected in the different phases of the circuit.

Y I shall-now describe the operation of the motor from circuit.

switch 2, the left-hand terminal of the moand brush 12; When this occurs the switch maniac double-pole switch 5, by conductor 36,2

through one side of the switch 6, by conductor 37 to the operating winding of switch 1, by conductor 38 to conductor 39 and thence to main line 26. The switch 1 thereupon responds and closes the motor circuit. The motor circuit upon closure of the switch 1 may be traced as follows: Une phase extends from the left hand terminal by conductors 40 and il through the contact- A of switch 1, by conductors 12 and 39 to line 26. Another phase may be traced from the center terminal of the motor by conductor 43 through contact B of switch 1, by conductors it and 45 to conductor 32 and thence to line 27. The third phase may.

be traced from the right hand terminal of the motor by conductor 16' to main line 25. The motoris thus set in operation driving the machine in one direction until the conducting portion of the ring 12 of the pilot switch 3 disengages the brush 12*. This results in opening the circuit of the switch 1, which drops, thereby disconnecting the However, just before this circuit is broken the conducting portion of the ring 13 engages the brush 13 which completes the energizing circuit of the switch 2. The circuit of the switch 2 may be traced from ring 11 of the pilot switch to ring 13 and brush 13*, by conductor 47, through one side of the switch 5, by conductor 48, through one side of the switch 6, by conductor 49, through the operating winding of switch 2 to conductor 38, which is connectedto line 26. Thus, as

soon as the switch 1 opens the switch'2 immediately closes again completing the motor circuit but reversing the flow of current therethrough. Upon closure of the tor is connected to line 27 instead of line 26 as previously set forth, while the central terminal is connected to line 26 instead of to-line 27 as above described. The motor being thus reversed drives the ma-- chine in a reverse direction until the pilot switch operates a sufficient distance to break circuit between the ring 13 and brush13 and again complete circuit through ring 12 1 is again energized, thereby again reversingthe .motor. This cycle of operation is repeated so long as. the switch 6 is left closed olrugtil one of the push buttons 7-8 is 0 use I too 1,141,154 x I a Assume now that the switch 6 is open and that push-button 7 is closed ThlS completes a circuit from conductor 32, by conductor 50, through the push-button 7, by conductor 37, through the opertaing winding of switch 1, thereby starting the motor, as already described. The motor will run in the same direction until the switch 7 is released, whereupon the switch 1 will be deenergized and disconnect the motor from circuit. Closure of the push button 8 completes a circuit from conductor 50, by conductor 19, through the operating winding of switch 2 to line 26, causing said switch to respond and start the motor in an opposite direction to that just described. The motor remains in operation until the push button is released. It will thus be seen that by means of the push buttons 7 and 8 the motor may be started in either direction at will without regardto the position of the pilot switch. While, of course, the switch 6 should be opened when it is desired to control the motor by the push buttons yet no injury could result from pressing the buttons while the switch 6 was closed. Assume now that it is desired to control the motor from the group pilot switch 4. The switch 5 should be thrown over to the right. This connects conductor 36, which leads .to

the operating winding of switch 1 to a conductor 52, which is connected to the brush 20 of one of the rings 20 which corresponds to the ring. 12 of the pilot switch 3. It also connects the conductor 48 to a conductor 53, which leads to the brush 19 of one of-the rings 19, which corresponds to the rin 13 of the pilot switch 3. The brush 18 0 the continuous ring 18 is connected by conductor 54: to conductor 34. Thus when the driving motor of the group pilot switch is set in operation and the switch 6 closed the motor M will be set in operation and thereafter periodically reversed in the same manner as that described in connection with the individual pilot switch 3. Assuming now that there were a plurality of se arate controllers such as that illustrate and that each controller was connected to one set of the contacts 19 and 20 by its respective throw-over switch 5 It is obvious that the group pilot switch would serve to periodically reverse all of the separate machines. As is well understood in the art, an electric motor in starting takes more current than when operating at normal speed. It will thus be seen that if a single group pilot switch was used to control a large number of machines and reversed all of the machines at the same time there would be a very heavy demand on the source of supply at the instant of reversal. To' meet this condition and to avoid excessive power demand upon the generating plant I have provided the group pilot switch and arranged the sets of circuit.

contacts 19 and 20 in a staggered relation. By connecting all of themachines to one pilot switch and staggering the sets of contacts it will be obvious that the machines will be reversed at difierent times accord ing to the angular positions of their respective sets 0 contact rings on the-shaft of the pilot switch. As illustrated, the pilot switch would reverse the machines successively and this of course would result in decreasing the load peaks.

The controller shown in Fig. 2 is essentially like that shown in Fig. 1 except for the switches controlling the motor. The motor shown in this instance is of the shunt wound type, being provided with an armature A and a field winding instance the motor is provided with starting F. Also inthis resistances R, R, R and R The motor is controlled by switches 60 and61'. Infpractice these switches may be of various diiferent types. As illustrated, each comprises four switch arms, 62, 63, 64 and 65, having cooperating contacts designated by the same reference numerals with the exponent a.

The switch members are mounted upona member 65. The remainder of the controller f is precisely like that shown in Fig. 1 except that circuits are D, C. instead of A. C. Also the pilot switches and other switches control the opertaing windings of the motor controlling switches 60 and 61 in the same manner as that previously described. It

will, therefore, only be necessary to describe the motor circuit connection.

Assuming that the switch 60 is first operated, circuit is first closed from line L by conductors 70 and 71 through switch arm 64 of switch 60, through the resistance R, by conductors 72 and '7 3, through the motor armature in a left hand direction, by conductors 74 and 7 5, through resistance R and switch arm 62 to conductor 7 6 and thence by conductor 7 7 to line L. The field winding F is permanently connected to line L and conductor 76 so that as soon as the motor circuit is closed the motor is set in operation but with the resistance R and R connected in its armature When, however, the switch 60 is operated to its full extent the switch arms 63 and 65 engage respective contacts 63 and 65 short circuiting the resistances R and R in two steps. This brings. the motor up to normal speed. The motor continues to operate in the same direction until the switch 60 is deenergized and the switch 61 is energized. This completes a circuit sistance ll from conductor 70 by conductor 78, through the switch arm 64- of switch 61, through reand conductors 79 and it through the motor armature in a right hand when the motor is started. However, as

soon as the switch 61 operates to its full extent the arms 63 and 65 thereof will engage their respective contacts, short-circuiting the resistance R and R in two steps thereby bringing the motor up to normal speed.

What l claim as new and desire to'secure by Letters Patent is:

l. In a controller for a plurality of electrio motors, in combination, a plurality of ent times.

reversing means, one for each motor, and automatic means for controlling said former means to eflect'operation thereof at difiier- 2. in a controller for a plurality of electric motors, in combination, a plurality of reversing means, one for each-motor and automatic means for controlling said former means to effect operation thereof successively to reverse the motors successively,

3. in a controller for electric motors, in combination, reversing means for. a motor, a device veffecting operation of said means periodically, a second. device adapted to similarly control a plurality of said means, and means for operatively connecting said reversing means to either of said devices to behcontr'olled thereby independently of the ot er.

t, In combination, a motor, reversin means therefor, a device operated by sai motor tocontrol said means to periodically reverse said motor, a second independently operated device adapted to similarly control a plurality of said reversing means, and means for operatively connecting said reversing means to either of said devices.

5. ln a controller for electric motors, in combination, reversing means, an automatically operated device associated with said means to cause periodic reversals of the motor controlled thereby, manually con-' trolled means associated said former means to operate the motor in either direction at will and means for disconnecting combination, electro responsive switches to cause the motor to operate in either direction, means controlling the energizing cir first mentioned means from said device! 6. ln a controller for electric motors, in

combination, motor reversing means, an automatic device for controlling; said means to periodically reverse the-- motor, manually operated meansto cause a; continuous oper'- ation of the motor in eithendirection at will and means for disconnecting said former as t at, its

combination, motor reversing means, an automatic device for controlling said means to periodically reverse the motor, manually operated means to cause a continuous operation of the motor in either direction at will, and means for disconnecting said former means from said device, said manually controlled means when released causing the motor to be stopped it said first mentioned means and said device are disconnected and restoring said first mentioned to the control of said device if said first-mentioned means and said device are connected.

8, In a controller for, a plurality of electric motors, in combination, a set of electroresponsive switches for effecting operation of one motor in either direction, an automatically operated device adapted to control the energizing circuits of said switches to eil'ect reversal of the motor controlled said first mentioned thereby periodically," a second automatically 1 operated device adapted to similarly cohtrol a plurality of said sets oi switches for the other motors, and a switch adapted to subj ect said first-mentioned switches to the control of either of said devices.

9. In a controller for a plurality of electrol a plurality of said sets of switches for the other motors, and a single double-pole,

double-throw switch for connecting said set of switches to either of said devices to be controlled thereby. V

10. In a controller'for electric motors, in combination, electro responsive switches adapted 'to cause the motor to operate in either direction, means controlling the energizing circuits of said' switches to cause periodic reversals of the motor controlled by said switches and control switches in circuit with the operating or"? said electro responsive switches to control the same at will independently of said second mentioned means. I

ll In a controller for electric motors, in

former means iii-circuit with trio motors, in combination, a set of electrothe operating windings of said electro responsive switches to control the same independently of said first mentioned means to cause continuous operation'of the motor in either direction.

12. In a controller for electric motors, in combination, electro responsive switches to cause the motor to operate in either direction, means controlling the energizing circuits of said switches to cause said switches to periodically reverse the motor controlledthereby, means for disconnecting the oper ating windings of said switches from said former means and swltches 1n circult with the operating windings of said electro responsive switches to control the same inde pendently of said first mentioned means to cause continuous operation of the motor in either direction, said control switches when released returning to initial position.

In witness whereof, I have hereunto subscribed my name in the presence of two Witnesses.

LE'WIS L. TATUM.

Witnesses F. H. HUBBARD, TEKLA BEST. 

